Transmission mechanism



Nov. 18, 1930. D. c. DOBBINS TRANSMISSION MECHANISM Filed April 21, 1930 3'Sheets-Sheet l I lllllli l 1930- D. c. DOBBINS I TRANSMISSION MECHANISM 3 Sheets-Sheet 2 Filed April 21, 1930' ea zz W m m I 1 I -l I I II II NOV. 18, 1930\- c DOBBlNs 1,782,343

TRANSMISSION MECHANISM Filed April 21, 1930 S Sheets-Sheet 5 gmmto'c Patented 1 8 ,1930 V r 1,782,343

, STATES PATENTF OFFICE I ,DONALD Domains, or cnnnrnrerninmno s if i i i TRANSMISSION MEoHAnIsM 7 a lication fi1et1Apri1.2 1, 19 30. serial noi 446,007.

The present invention relates to change high and reverse gear drives -may be readily speed transmissions of theshiftable gear type obtained by shifting one ormore coupled for motor driven vehicles and the like and pinions, herein designated at 11 and 12int0' aims generally to improve the mechanism for engagement with direct, intermediate, low

shifting said gears." j and reverse -ears respectively as described in M re particularly the invention relates to my said copending application, and as'readthe improvement of means controlled solely ily understood. In this manner desired by the depression of the, clutch pedal .for sucdriving speeds may be obtained for operacessively shifting the change speed gearing ti'vely connecting in driving relation a clutch loprogressively, optionally in speed increas ng controlled driving shaft 13 with thedriven or decreasing direction, through aseries of shaftl. i

different speeds, as more generally embodied As is usual in such devices, and as disin my copending application Serial'No. 433,- closedin my copen'ding application above 981, filed March 7,1930. i i I referred to, the shifting of the pinionsll To this end thepresent invention provide and 12 mayladvantageously be effected by improved and simplified mechanism for the yokes 15 and '16, or the like, suitably of bell shifting of the shiftable gears controlled crank form, pivotally mounted in the casfrom the clutch pedal. ing 10. upon posts 15 and 16?, and operallumerous specific objects and advantages tively connected to controlling cams 17 and of this invention will be readily apparent 18, rotatably mounted in the casing. The from the following description of apreferred cam 17 has a continuous peripheral rim 20. embodiment of the invention which has been operatively controlled by gear shifting yoke selected for illustrative purposes in'the ac- 15 to shift the pinion 11 from its neutral or companying drawings, wherein idle position (asshown in Fig. 1), forward- Fig. 1 1s a plan view of my improved transly for direct drivln connection with gear mission; I 19, or rearwardly Ior drlvlng connection 2 is a vertical sectional view thereof with an. intermediate or second speed gear,

taken on the line 22 of Fig. 1 looking in the not shown. The cam 17 has a second discondirection of the arrows, V tinuous rim 21 running between bosses 22 so Fig. 8 is a vertical sectional view taken on on the yoke 16 for shifting the yoke and ,its so the line 33of Fig. 1 looking in the direction pinion. 12 into driving engagement with low f the arrow Y speed or reverse gears, as iswell understood.

Fig. 1 is a vertical transverse sectional Progressive partia ations of the cam i t ke on th li 4. 4 f-Fig; 3-; a m embers 1 and 18 to s t the pinions 11 and Fig. 5-is a similar view taken'on the line 12.1nto desired position, are preferably ef- 5-5 of Fig. 3; and v fected and controlled partly by and during Fig. 6 is a diagrammatic or plan view of depression of the clutch pedal (not shown) to the controlling cams for actuatingthe shiftfirst shift the pinions into neutral position, able gear 'yokes. and then automatically upon release of the r In the illustrated embodiment of the 'inclutch pedal, to shift the pinions 1.1 and 12 vention the transmission casing 10 houses into engagement with the next higher or next 7 the transmission gears and shifting mechalower speed gear, depending upon Whether nism, so that the entire mechanism may be it is desired to increase or decrease the speed assembled and readily installed as a unitin of the vehicle. s I 1 the'vehicle as in my copending application As in mycopending application above re-- above referred to. ferred to, the cam 17 is keyed upon a shaft 23 The transmission gearing. may be of any jourrialled in suitable bearings in the trans-' conventional or standard design, preferably missionasing, and is given partial rotation of the shiftable gear type, wherein selective to effect shifting of the gear shifting yokes driving speeds through low, intermediate, by means of rotary members such as ratchet Wheels 24 and 25 reversely arranged upon a sleeve 26 splined to the shaft The rotary member 24 is adapted to be rotated in a counter-clockwise direction to impart ilar partial rotation to the cam 17 for shifting the transmissiongears in speed increasing order,

and the rotary member 25 is adapted to be. rotated in a clockwise direction to mipart.

similar partial rotation to the controlling cams for shifting the gears in speed decreasing. order. A third rotary member 27 connected to the reversing cam 18 and sleeved in a counter-clockwise,direction to shift the.

upon the shaft is adapted to rotate the cam pinion 12 into and out of engagement with the reverse driving gear 14s disclosed in my said copending application, the rotary members are manually shirt-able along the shaft 23 by meansof a manually operated sh tting fork 281nto selectivepositmn ior speed increasing or decreasing or reverse shitting positions. I

The clutchpedal may be of the usual well known type, fixedlysecured to a shaft 30 journalled in the casing 10 (see FigsI2 and 3), and carrying a lever 31 connected by link to an actuator on a stub shaft 84 mount ed in the casing 10. The actuator is preferably in the form of a three armedvlever, as

, shown, having one arm 35 shaped as a cam and engaging roller 36 on arm 3"? connected to the clutch release shaft 38, so that the initial depressing: movement 01 the clutch pedal operates to hold the clutch disengaged-andprevents the clutch from becoming engaged until the final release of the clutch pedal.

My present invention is an improvement a guide 42 toward the rear of the transmi sion casing; The forward end of the carriage maybe in the formof a sleeve 43 surrounding the guide 42 and its movement away from the ratchet wheels 24, 25, or 27, is limited by .means of a suitable stop lined on the guide.

A coiled spring 45 surrounding the forward circular portion of the guide 42 is positioned between the sleeves 43 of the carriage and a collar 46 on the guide so that movement of the carriage rearwardly by the action of the actuator arm 35 compresses the spring which acts to return the carriage to the normal position upon release of the clutch pedal.

The carriage may be of any formsuitable for its purpose, but as here illustrated, comprises a frame having arms 47 extending rearwardly from the sleeve portion '43 on opposite sides of the guide 42 and terminating ina rearward sleeve 48 surrounding the squared end 49 of the guide better to guide and position the carriage 1n 1ts reciprocative movement. The carriage 41 also may be' tive connections between the reciprocating carriage 41 and the rotary members 24, 25 or 27! Each set of actuating pawls comprises a pushing pawl51 pivotally connected as at 52 to the bracket and provided at its free end with aseat portion 53 adapted during rearward travel 01' the carriage to engage and push the rotary members 24, 25 or 27 through one eighth revolution to effect similar partial rotation of the respective cams and shift the gears from its previous gear drive into neutral position. An oppositely disposed pull pawl 54 pivoted as at 55 to thebracket 50, and provided at its free end with a hooked end 56 is adapted to engage the ratchet wheels 24, 25 or 27 upon return ofthe slide by the spring 45 and turn them an additional 45 degrees, to effect shifting-the transmission gears from neutral position to the next higher or lower speed as the case may be. A spring 57 con nee-ting the opposed pawls of each set serves to hold them in operative position for actua tion of the wheels 24, 25 or 27.

The rotary members are alike in constructin and, in the illustrated embodiment of the invention, which contemplates greater revolutions of the cams 17 for shifting from one i s used to the next ma bein the form of fourarm ra tchet or star wheels having cylindrical heads 58 on the ends of each arm adapted to be engaged by push pawls, and recesses 59 in the webs adjacent the heads 58 and adapted to be engaged by pull pawls.

Thus it will be apparent with the ratchet wheels 24, 25. and 27 in the position shown in Fig. 1 with the wheel 24 in alignment with the pawls 51 and 54 on the left side of the carriage as viewed in Fig. 1, and the pinions 10 and 11 in neutral position, that on rearward movement of the carriage 41, the lower push pawl 51 1 (see Fig. 3) will engageone of the cylindrical. heads 58 of the ratchet-wheel 24 and rotate the ratchet wheel and its connected cam 17, forty-five degrees. During this movement the cam rims 20 and 21 are moved from positions a and a to I) and Z) (see Fig. 6) without etl'ecting shifting of the pinions 11 and 12 because of the straight sections of the hue 20 and 21 between these points. The carriage 41 is at this time at the ends of its rearward movement, and a semi-cylindrical seat 60 on arearwardly projecting portion of the bracket 48 (see ig. 3) engages the adjacent aligned head 58 of the wheel 24 and holds it against accidental shifting until the slide ispermitted to move forwardly on release of the clutch pedal. The head 58 in ad vanc'eofthe hooked endof the-pull has-passed theend ofihe pawl, whichis-theii positioned, by reason of spring 57, to engage,

in the seat 59 of thehe'ad;

Upon release of theclutch pedal, the

spring 45 returns the carriage a1 to its normal position forwardly in'the transmission casing 10, causing the pullpawl 54; in engagement with the recess-59 of one of the heads-58 of the'wheel 24, to rotate the wheel an additional'forty-fivedegrees, thus rotating the cam 17 and its rims 20 and 21 from b and b to c and too to cause the cam lobe 21. o'lthe rim 21 to shift the yoke 16; and pinion- 1 12 into engagement with the first speed'gear (not shown). The next succeeding depresof: the clutch pedal, rotates the cam "17 an additional forty five degrees (from 0 and 0 to (Z andd) returning the pinions 11 and 1.2 to the neutral position, andupon release of the clutclr oedal, jrotates the canr l'? further an elghth revolution (d und d to e and e") to cause the cam lobe '20 of therim 20 to shift yoke 15 and pinion 11 into engagement with the second or intermediate speed gear. The next depression of the "clutch pedal and consequent eighth revolution ot cam 17, (from c and 6? to fend returns both pinions to neutral position, and release of the clutch pedal permits an additional eighth,revolution'of the cam 17 (from f and f to g and g) and causes cam lobe 20? to shift yoke 15' and pinionll into engagement -with the direct or high speed gear.

' Should it be desired to shift thefgears successively n descending order, the sleeve 26 may be manually shiftedto the left viewed in Fig. I) by means of the shifting 01 528, as in my said copending application,

I so as to move the ratchet wheel into alignment with the other'set ofpawls which are reversely' arranged to rotate the Wheel 25 and cam 1'? in a direction opposite to that 111st dlscu'ssed.

' Similarly, shifting :of the sleeve 26 to the right, as viewed in Fi .1, brings the reverse gear ratchet wheel 27 into alignment with the first mentioned pawls 51 and 54, causing partial rotation of the wheel 27 and cam 18,-"to cause shifting of the pinion 12 "first, to neutral position, and then into engage inent with'thereverse gear drive;

- As ahove'stated, the wheels 24, 25 or 2 are restrained from accidental'shifting out of their neutral position byengagement of the seat in the arm 4: 8 with-one ofthe cylindrical heads 58, when the carriage is at the end of its rearward movement Similarly a seat 62 on the rearward sleeve 48 of the carriage engages an adjacent head '58 of the wheels 24, 250! 27, (see Figs 2 and 3) when the carriage is in its forward or nor mal position, and'p'revents accidental shift mg of the wheels, cams or yokes to move' t'he' i s'q 12 O f their selected driving position. Y a

Advantages of my inventionresidein the; simplicity of construction. permitting quick shifting of gears from one speed to'the next on'a singledepressionof the clutch pedal. The gears are always neutralized at mid:

shift-(i. e. when the pedal is completely de-' pressed) which enables the operator to de-. terminewith ease and certainty the time for f pausing to permit the rotating pinionsto lose their inerti'ajbefore moving them into. meshing engagement with .the next. speed gear.

the worlrof shifting the gears is effected quickly during final depressing movement of the pedal and during the initial releasing movement thereof, thus avoiding idle movement ofthe pedal and rendering a greater portion of. pedal movement available forlits, normal function of releasing and ,re-engag ing the clutch.

2: claim:

1. In a shift-able change speed gearing including shiitable gears, a clutch. therefor, means for shifting said gears successively into engagement with different speed and direction cam means for said shifting means,a foot pedal, andconnection's asso- Furthermore, according to my invention,-

eiated with said foot pedal for effectingdis:

engagement of said clutch upon initial depression of sald pedal and effecting shifting of said gears to neutral position upon final de uression of said edal means for eii'ectin l a shiftim of said ears to the next 'ro ressive b t? b speed upon initial release of said pedal and engagement of said clutch upon hnal release thereof and after enga ement of said drivin n, b 6

ly shifting said gears into engagement suc-L ce vely with diiferent-speed and direction g means, a clutch for said gearing, a

of the clutch upon initial depression of said dah'and then e'l fecting movement of said cam to shift sald gears to neutral position upon further depressing-movementlof said pedal, and separate connections associated with said pedal for shifting said gears into drivin g engagement with selected gears upon" releaseo f said pedal, the said first named means being operable to shift said gears through successive speeds automatically withoutananual preselection for forward drive.

3. In a change speed gearing, including shiftable driving pinions, means for seleccontrol pedal therefonand connections associated with saidpedalgfor efi'ectmg release means for controlling. said gear r tively shifting said figears into engagement successively with di erent speed and direc: tion gears, cam means-for controlling said gearshifting means, a clutch for said gearing, a control pedal therefor, and connections associated with said pedal for eflecting release of the clutch upon initial dBPI'GSSlOII of said pedal, and then effecting" movement of said cam to shift said gears to neutral. position upon further depressing movement of.

said pedal, and separate connections associatedwith said pedal for shifting saidgears into driving engagement with selected gears upon release of said pedal,.and whilelthe, clutch is held disengaged, the said first named means being operab e to shift said gears through successive speeds automatically without manual preselection for forward drive.

4. In a change speed gearing, including shiftable driving pinions, means for selectively shifting said gears into: engagement successively with different speed anddirection gears, cam means for controlling said gear shifting means, a clutch for said gearing, a

.control pedal therefor, and'connections associatedwith said pedal for automatically effecting disengagement of the clutch, shifting of the gears to neutral, and then into engage.

, ment with the 'selectedagear and engagement 'preselection for forward said pedal including push and pull pawls for engagement with said ratchet wheels to. effect shifting of said gears first into neutral position, and then into engagement with a selected driving gearduring a single depression and. release of said pedal, said connections acting automatically to disengage. said clutch during shifting of said gears.

6. In a change speed'gearing, including shiftable driving pinions', means for selectively shifting said ears into engagement successively with different speed and direction gears, cam means for controlling said gear shifting means, a clutch for said gearing, a control pedal therefor, ratchet wheels connected with said cammembers for rotation therewith, and connections associated with said pedal including push andpull pawls for engagement with said ratchet wheels to effect successive partial unidirectional rotation of automatically.

drive.

said ratchet wheels and camsforshifting of said gearsfirst into neutral position and then into engagement with a selected driving gear during a single depression and release of said pedal, said connections acting automatically to disengage said clutch during shifting of said gears. a

7. In a. change speed gearing, including shiftableldriving pinions, means for selectively shifting said gears into engagement successively with different speed and direction gears, cam means for controlling said gear shifting means, a clutch for said gearing, a control'pedal therefor, ratchet wheels connected with said cam members for rotation therewith, and connections associated with said pedal including oppositely disposed push and pullpawls for'engagement with said ratchet wheels to effect successive partial unidirectional rotation of said ratchet wheels and cams for shifting of said gears first into neutral position and then into engagement with a selected driving gear duringassingle depression and release of said pedal, said connections acting automatically to disengage said clutch during shifting of said gears. i

8. In a change speedgearing, including shiftable driving pinions, means for selectively shifting said gears into engagement successively with different speed and direction gears, cam means for controlling said gear shifting means, a clutch for said gearing, a control pedal therefor, and connec tions associated with said pedal for acting directly to automatically effect disengage ment of said clutch and, shifting said gears into neutral position, and further means acting automatically to shift said gears into driving engagement with the next successive higher or lower gear during release of the pedal, and prior to engagement of said clutch, the said first named means being operable to shift said gears through successive speeds automatically without manual preselection for forward drive.

9.In a change speed gearing, including shiftable driving pinions, means for selectively shifting said gears into engagement successively with different speed and direc tion gears, cam means for controlling said gear shifting means, a clutch for said gearing, a control pedal therefor, and connections associated with said pedal for acting directly to automatically effect disengagement of said clutch and shifting said gears, into neutral position, and springmeans acting automatically to shift said gears into driving engagement with the next successive higher or lower gear during release of the pedal, and prior to re-engagement of said clutch, the said first named means being operable to shift said gears through successive speeds automatically without manual preselection for forward 10. In a changespeedgearing, including shiftable driving pinions, ine'ansifor manually pre-sele'cting the. order and direction of iigear shifting "means for-successivelyshifting a v i I i '14. In a change speed gearing including v said pinions intoengagement with successive driving-gears automatically throughicycles to and from neutral position either pie-selected speed increasingor speed decr asing order "for forward drive or for reverse drive, cam

members torcontrollingsaid shifting means,

andmeans for impartingsuccessive partial movements tOGfiJlClCtllll' members for auto matically shiftin'g said gears to neutral and then into engagementwith the next higher or lower speed gear, l

11. In change speed gearing, including s lift-able driving pinions, means for manually pre-selecting the order and direction r of gear shifting, means for successively shift ing said pinions into engagement with successive driving gears automatically through cycles to and from -neutral"- position either pie-selected speed increasingor speedde creasing order for forward drive or tor reverse drive, rotatably mounted canimembers for controlling said shiftingmeans,a foot pedal, and means controlledbyf'said foot pedal for? imparting partial rotation to the cam members tO'jShlft saidgearsinto neutral position, during depression of the pedal,-and

further means independent of the pedal for automatically impartingfcontinued partial vrotation of said cam members to shift said gears into engagement with speed gears of I the next higher or lower order upon release of the pedal. j a

12. In a change speed gearing, including shiftable driving plnions; means for selectively shittingsaid gears into engagement successively with dliierent speed gears in speedincrea-singor decreasing order, a clutch for said gearing, a control pedal therefor, and means for imparting quarter revolutions tothe cam members ,uponsingle depression and release of said clutch pedal to effect successively shifting of said gears first into neutral position and then into. engagement with the speed gears of the next higher or lower order,the said first named means being operable to shift said gears throughsuccessive speeds automatically without manual preselection for forward drive.

.13. In a change speed gearing including sniftable driving pinions, means for manu ally ire-selecting the order and direction of gear shitting, means for successively shitting said pinions into engagement with successive driving gears automatically through cycles to and from neutral position either pre-selected speed increasing or speed decreasing order for forward drive or for reverse drive, 11 eans for controlling said gear shifting means, and means for imparting successive movements to said controlling means, comprising a reciprocable carriage, and means on said carriage adapted for engagement with said controlling means to mpart partial movement thereto during opposite reciprocations therefoiz I i shitta'bledrivi g pinions, means for manucessive driving gears automatically through cycles to and from neutral positi'oneither pre- QGlQCtGCl"SPGGClYlllCI'GHSlHg or speed decreas- 'ing oroer'for forward drive or for reverse drive, rotatable means for controlling said ge'ar shifting means, and means for impart ingirotation to said control means including v a reciprocable carria eand connectionsassociated with said carriage adapted for engagement with said control means to efiect automatically unidirectional rotation of said.- :control means during opposite movements of saidcarriage I 15. In a change sieed gearing including shiftable driving P11110118, means for manuall-ypre-selecting the order and direction of gear shifting, means for successively shiftfling said pinions into engagement with succe'ssive driving gears automaticallythrough cycles to and from neutral position either preselectedrspeed increasing or speed decreaslngorder for forward drive or for reversedrive, rotatable means for controlling said gear shifting means, a clutch for saidgearing, a control pedaltherefor and means for imparting partial rotation of said control means to effect shiftingiofsaid pinions for engagement with one "gear, through neutral intoengageanent with the next higher or lower gear durg asingle depression and release of said fpedal, comprising a reciprocating, carriage andconne'ctions associated with said carriage adapted forengagement with said control means to effect automatically unidirectional partial rotation thereof, during opposite movement of said carriage.

l6."In a change speed gearingincluding shiftable" driving pinions, meansufor" selectively shifting said pinions into engagement successively with difier ent speed or direction gears, rotatable means for controlling said gear shifting means, a clutch for said gearing,-a control pedal therefor and means for imparting partial rotation of said control meansjto eiiect shifting of said pinions :tor engagement with vone gear, through neutral into engagement'with the next higher or lower gear during a single depression and 1e leaseof said pedal, comprising a reciprocating carriage, push pawls associated with'said carriage.and'adapted to engage said control means and effect partial rotation of said conrol neans during one movement otsaid car- 'iage upon depression of said pedal, and pull awls associated with said carriage adapted o engage control means and effect continued partial :unidirectional rotation of said control means during opposite movement of the carriage upon release of said'clutch pedal,

17. In a change speed gearing including shiftable driving pinions, means for selec tively shifting said pinionsinto engagement successively with di erent speed or direction gears, rotatablemeans for controlling said gear shifting means, a clutch for said gearing, a control pedal therefor and means for V imparting partial rotation of said control means to effect shifting of said pinions for engagement with one gear, through neutral into engagement with the next higher or lower gear during a single depression and release of said pedal, comprising .a reciprocating carriage, push pawls associated with said carriage and adaptedto engage said control means and effect partial rotation of said control means during one movement of said carriage upon depression of said pedal, and pull pawls associated with said, carriage adapted to engage said control means and effect con-' tinued partial unidirectional rotation of said control means during opposite movement of the carriage upon release of said clutch pedal and spring means adapted to actuate said carriage in its return direction during release of said clutch pedal.

18f In a change speed gearing, including shiftable driving pinions, means for manu ally pre-selecting the order and direction of'. gear shifting, means for successively shifting said'pinions into engagement with successive driving gears automatically through cycles to and from neutral position either pre-se lected speed increasing or speed decreasing order for forward drive or for reversedrive,

movement in one direction thereof for effecting partial rotation of said ratchet wheel and cam member to automatically shift said pinion to neutral position, and operative during opposite movement of 'said pedal for automatically shifting said pinions into engages ment with the next higher or lower speed gear. 5

' 20.111 a change speed gearing having shiftabledriving pinions, means for manually pre-selecting the order and direction of gear shifting, means for successively shiftmeans for effecting shifting of said pinions into engagement with the next higher or lower speed, gear during movement of the carriage inthe opposite direction on release of the clutch pedal. i V

In testimony whereof, I have signed my name to thisjspecification. 1

' f DONALD C. DOBBINS.

a cam member for controlling said shifting means, a ratchet wheel connected with said cam member for rotation therewith, a clutch for said'gearing, a control pedal therefor, and connections associatedwith said clutch pedal for imparting-successive partial movements to said ratchet wheel and cam memher for automatically shifting said pinions to neutral position, and means controlled upon the release of said clutch control pedal for shifting said pinions into engagement with next higher or lower speed gear.

'19. In a change speed gearlng, lncludlng shiftable driving pinions, means for manually pre-selecting the order and direction of a gear shifting, means for successively shifting said pinions into engagement with successive driving gears automatically through cycles to and from neutral position either pre-selected speed increasing or speed decreasing order for forward drive or for reverse drive, a cam member for controlling said shifting means, a ratchet wheel connected with said cam member for rotation therewith, a clutch for said gearing, a control pedal therefor, and connections associated withosaid clutch pedal and operative during 

